The present invention relates to a cleaning device for beverage drafting and dispensing systems, especially dispensing systems for carbonated beverages such as sodas, colas and fruit juices, as well as beer, utilizing primarily water and a liquid chemical cleaning agent which can be induced into the drafting lines from a storage container, and from which it can be removed again after a prescribed settling time.
Such a cleaning device does not presently exist, at least not in the configuration of the present invention with its attendant advantages. A fully automated device is described in applicant's co-pending application, Ser. No. 07/523,428. Although this device is functionally related to the present invention, the former is, however, significantly more complex than .the latter. With the exception of standard, pressurized storage containers for the commercially diluted liquid chemical cleaning agent which can be connected manually to the beverage line to be cleaned, no other devices or apparatus facilitating or easing the handling of the cleaning process of such beverage dispensing systems are known. In reality, the necessary cleaning process for such beverage lines and the associated drafting and dispensing equipment is completely manual. Whenever a particular beverage container is emptied, the operator is required to manually remove the dispensing adaptor and place in on the connecting valves of a new, full container.
Depending on the individual principles of the operating establishment, the recommendations of the manufacturer and/or government regulations, the drafting lines and/or the dispensing system should actually be cleaned during this container exchange process. For the purpose of such cleaning (and assuming that the appropriate pressurized containers with cleaning agent are installed at the site) the dispensing adaptor should actually be connected to the pressurized container containing the liquid, the chemical cleaning agent being properly diluted for the cleaning process. Since the cleaning agent container is properly pressurized, the operator now would return to the tapping cock and initiate the flow of cleaning agent by opening the tapping cock until cleaning agent would flow from the cock. The cleaning agent is generally easily recognizable due to a apparent coloration, e.g. blue.
As soon as such cleaning agent is dispensed, the operator would close the tapping cock again and allow the agent to settle in the beverage line, depending on brand and degree of dilution of the cleaning agent, for 15 to 30 minutes. After that period, the operator returns to the container site, and replaces the adaptor from the pressurized container containing the cleaning agent to a new beverage container which is also pressurized. Upon his return to the tapping cock, the operator again opens the cock, thus allowing the beverage to push out/flush the preceding cleaning agent in the beverage line. When the liquid flowing from the cock resumes the color of the beverage, the operator generally discards several portions of this beverage for safety reasons and for avoiding serving a beverage/cleaning agent mixture. Thereafter, the tapping process resumes normally.
It is easily understandable that the interruption of the regular tapping and dispensing process for such cleaning routines, requiring anywhere between 15 and 35 minutes, is hardly tolerable, especially at peak times and especially when the establishment operates only one tapping line for each type of beverage served. The mere exchanging of an empty beverage containers with a new, full one is interruption enough for the operator (or his customers), especially when the beverage containers are located remotely from the dispensing site, such as in basements, as is often the case.
It is also not very convenient for the operator to perform the cleaning routine for each beverage line at the end of his operating shift, which is many times exhaustive and lengthy, by moving back and forth between container and tapping site three times per line, taking waiting periods of 15 to 35 minutes into account for each line. Due to the expense of the specialized, pressurized container containing the diluted cleaning agent, it is very unlikely that an establishment will maintain one of these containers for each beverage line operated. It is also very unlikely, since in most cases not economically feasible, that any but the largest establishments would afford a separate, dedicated "cleaning operator" whose sole responsibility is the routine cleaning and maintenance of the beverage lines.
The logical consequence in the field is that beverage lines are not, or at least hardly ever, cleaned properly and frequently enough to assure continuous high quality of the beverages dispensed as well as highest possible hygienic status of the equipment and, therefore, compliance with the established government regulations. This is especially negative since the beverages dispensed, e.g., sodas, juices, beer, etc., are essentially food substances, and, as such, are subject to mutations or changes unless specific precautions are taken. These changes, though many times undesirable, are avoidable. One example are the changes caused by enzymes and bacteria when the food or beverage is exposed to air. Whenever these change processes take place in sodas, juices or beer, it results in significant impairment of the quality and noticeable change in taste.
Sodas, juices and beer furthermore contain substances which deposit a slime, skin or layer on the surfaces exposed to the beverage. Infrequent cleaning of such surfaces, e.g. tapping lines, dispensing systems, etc., results in a significant enhancement of such deposits. Regular and frequent cleaning with appropriate liquid chemical cleaning agents, however, results in the removal and the subsequent prevention of such deposits and/or keeps such deposits within negligible tolerances.
With the exception of the traditional method for the cleaning of beer tapping systems used in Germany and other parts of Europe, namely, the use of water and abrasive rubber cleaning balls, the present cleaning process for beverage lines, esp. for sodas, colas and/or juices does not utilize water, and, is not intended to incorporate water as an additional cleaning agent for the tapping lines, the tapping cocks, the container adaptor and/or other parts of the dispensing equipment, unless one manually disconnects the beverage lines and connects the entire system to a water supply.
Sodas and colas especially, however, do contain more or less significant amounts of sugar, glucose or other, similar substances with the specific property of depositing themselves on exposed surfaces even under flowing conditions, not to mention at still condition, and to subsequently crystalize. Primarily sugar crystals have a tendency to deposit on the surfaces of dispensing lines and system components and to develop rather resilient crusts. On the inner surfaces of tapping lines, such crusts may even be tolerated, although they are definitely detrimental to the quality and, sometimes, the dispensing speed of the dispensing process. In particular, excessive foaming of the beverage and excessive and undesirable release of carbonation due to higher flow resistance in the lines take place. Moreover, existing sugar crystals perpetuate the formation of new crystals. These crystals are even more disconcerting where moving parts of the dispensing equipment and/or seals and gaskets are concerned. The friction and/or penetration of the sugar crystals can easily result in blockage of such moving parts, their excessive and premature wear, as well as in leakages.
Based on the above situation and the associated concerns, the present invention provides a device which allows for the automatic, remote-controlled initiation of the cleaning process with a specific, liquid, chemical cleaning agent as well as for the combined, controlled cleaning and/or flushing process with clean tap water.
The above object has been achieved in accordance with the present invention with a cleaning device comprising a hydraulically controlled change valve, controlled via three solenoid valves, pressurized with tap water and enclosed in a valve housing which contains a hydraulically movable piston which, in the operating "tapping" position, provides the first flow. Such flow is intended for the beverage. On the lower part of the valve housing, the beverage container adaptor equipped with a check valve is connected and on the upper part of the housing, a line connection is made with the beverage line leading to the tapping cock. This connection through the device is accomplished by a channel surrounding the piston in the tapping position.
Furthermore, in the operating "cleaning" position, the valve provides for a second flow, such flow being intended for a water/cleaning agent mixture. On the one side of the housing, a line with such mixture is connected to the upper part of the first flow through the device and into the beverage line, while the lower part of the first flow to the beverage container adaptor, and thus into the container, is blocked by moving the piston and thus disconnecting the channel.
Furthermore, an additional hydraulic control connection (tap water connection) is made on the opposite side of the housing. The hydraulic action of the connected tap water is controlled with the three solenoid valves, the pistons of which are retained in the rest position via check valves. These check valves in the rest position provide for a connection via a channel between a valve exit opening and a valve side opening and in the opposite "operating" position, with excited solenoid, provide for a connection via a channel between a valve exit opening and a valve entry opening.
According to another aspect of the present invention, the entry opening of two of the solenoid valves is connected to the pressurized tap water source. The exit opening of one of the two solenoid valves functions as the "tap- or normal position valve," through the hydraulic control connection, and is connected with the side connection of the housing and thus with the piston. The exit opening of the other of the two solenoid valves, functions as the "cleaning- or flushing valve", and is connected to the line carrying the cleaning mixture and thus to the other side connection of the housing or the piston. The cleaning mixture carrying line leads through an adjustable dilution/dispensing device based on the Venturi-principle. The third solenoid valve functions as the "cleaning agent valve", and is integrated between the exit opening of the "cleaning - or flushing valve" and the entry to the dilution/dispensing device to form a by-pass connection to the side opening of the third solenoid valve. The exit opening of the third solenoid valve is connected with the cleaning agent entry opening of the dilution/dispensing device, and its entry opening is connected to a gravity line of a cleaning agent retention container. The side openings of the other two valves are connected with a drain hose. The solenoids of all three valves are connected to a common electrical power supply, allowing the initiation/switching of each valve via a designated switch, preferably located on a switch board near the tapping cock/dispensing site.
The cleaning device of the present invention now allows alternate connection of the tapping line either with the beverage container or the water line depending on the position of the piston. All that is required to do so is the initiation of the switches at the tapping cock which operate the appropriate solenoid valves. This eliminates the cumbersome process of the operator having to move between container and tapping site and to continuously connect and disconnect various lines, in order to, for example, flush a beverage line for cola with water and to keep the line filled with water overnight in order to dissolve possible sugar crystal in the line. This very beneficial process can be accomplished fully automatically with the push of a button.
When the solenoid valve for the chemical cleaning agent is initiated and the piston is moved to the "cleaning" position water will absorb cleaning agent which is injected into the line. The gravity injection is adjustable. The complete filling of the line with the water-cleaning agent solution or mixture becomes evident when colored liquid flows from the tapping cock. The cock can than be closed, allowing the solution to settle in the line for the prescribed lengths of time to complete the cleaning process. By again switching the cleaning valve, the operator can easily flush with clean water, thereby eliminating the need to flush with beverage as is common with the present manual process, and resume the dispensing process at leisure or the next morning, carrying only water in the lines during rest hours. This assures that no valuable beverage is being discarded, a common problem, especially with beer lines, amounting to a sizable amount depending on the length of the lines.
The cleaning device of the present invention for beverage lines assures a time and labor saving cleaning process and allows the cleaning and flushing of any beverage lines at any time. It also results in significant cost savings for the establishment, namely, no beverage loss, no need for specialized, pressurized containers for cleaning agent solution and associated equipment, elimination of regular, professional cleaning services for beer lines; etc. Significant space savings also result due to the elimination of the pressurized containers for cleaning solution and substitution by a much smaller container of concentrated cleaning agent. Due to the use of the Venturi dilution-dispensing device and the fact that the piston is operated by water pressure only, it is required to have a pressure controlled water line on site.
The configuration of the cleaning device of the present invention includes the beverage entering on the bottom and the cleaning liquid entering from the side. The flow principles of the device result in the fact that the lower portion of the device itself, as well as the adaptor to the beverage container, are not being cleaned in the normal process describe above. Although this is a relatively short line, it is still recommended to clean this section occasionally, such as over night or when changing a beverage container.
Another aspect of the present invention is the use of an adaptor integrated into the cleaning process. To perform such a complete or total cleaning process, the adaptor is configured to be removed from the beverage container and connected with a separate receptacle upon which the regular process is performed. To reinitiate the dispensing process, the procedure is reversed.
Another feature of the present invention is the arrangement of the solenoid valves in a functional block unit, allowing on the one side the connection of the adjustable diluting-dispensing device for the cleaning agent while allowing one each connection on the bottom for pressurized clean water or drain water. On top, provisions are made for hydraulic control water (i.e., set water) and hydraulic control water-cleaning agent mixture. In addition, the base block has a combination pipe housing the lines for water, drain and cleaning agent and allowing for the sideward connection of additional devices for the construction of multiline configurations.
Another advantageous aspect of the present invention involves the change valves piston-cylinder which is hydraulically activated. A significant benefit is the fact that the piston is actually activated by the hydraulic action of either the cleaning water itself or the mixture of cleaning water and cleaning agent. This results in the fact that the liquid used is either beverage or cleaning liquid, assuring that no foreign agents are introduced into the system and that all normally floated cavities are consistently cleaned. Depending on the position of the solenoid valve, the piston is activated as a hydraulic cylinder from either side.
In this respect the reliable sealing of the two flows i.e., drafting and cleaning, against each other is critical to avoid any undesirable mixing of the two during the routine dispensing or cleaning process. A good churning and whirling of water and cleaning agent is, however, critical for the effectiveness of the cleaning process. It is important that the water-cleaning agent mixture gushes across the gasket of the piston and then flows through the jet-like gap to reach the area between the throat and the piston bore. The flow through the jet-like gap results in an intensive churning sufficient to assure effective and efficient cleaning of all associated components, and ensuring a continuous exclusion of any encrusting.
The device of the present invention is also equipped with a beverage container connection adaptor with check valve. The lower end of the valve housing is equipped with a bore, which at its upper and narrow end, connects into the vertical bore of the drafting flow. Underneath is a set-bore which incorporates the upper, wider, cylindrical end of an otherwise conical connection piece. This connection piece functions as an abutment for the coil spring and, in its center, has a bore for the pin which disconnects the lower conical nipple resting on the counter surface at the connection piece of the tube jointing sleeve held under pressure of the coil spring by way of an elastic seal. A downward protruding pin on this cone is configured so that it comes to rest on a counter pin of a coupling- or connecting unit or receptacle of the beverage container when the adaptor is locked in place with a quarter-turn fastener. That configuration results in the mutual cancellation of two spring forces, allowing an open flow of beverage through the adaptor and cleaning device. Upon disconnection of the adaptor, the two valves which had been connected via pins, i.e., the one on the beverage container and the one on the change valve, return to the sealed position. This prevents any liquid from escaping the change valve or the dispensing system. Therefore, after the adaptor had been attached to the receptacle and adequately floated with water or cleaning solution, it may then be removed to allow the settling process while disconnected from the receptacle and thus to allow the cleaning of more than one adaptor with only one support receptacle for the process of cleaning entire dispensing multiline systems, a benefit which also saves time. The individual adapters can, after the settling period, be replaced on the beverage containers in which situation the beverage would be used for flushing and rinsing. Alternately, pure water can be used in a renewed cleaning/flushing process after the settling time.
Another key benefit of the present invention is the fact that the device can be used for more than one dispensing lines without requiring extensive additional equipment. One embodiment of such a multiline construction provides that each beverage line requires only the basic change valve as the adaptor to the beverage container while the hydraulic set-water line and the set-water/cleaning agent-line of each change valve are connected to a common base block. The connection of such can be made by appropriate fittings such as multiline distributors, cross pieces or similar devices or it could be configured to provide for T-junctions from one change valve to the next.
In a multiline embodiment of the present invention, switching to, e.g., the "drafting" position would result in all change valves moving into the drafting or dispensing position due to the fact that the appropriate solenoid valves cause the cylinders to change position. With a multiline construction, all interconnected beverage lines are cleaned simultaneously, initiated or controlled from one switch box near the dispensing cocks. This also means that the individual steps in operating the cleaning device (namely, changing positions of cylinders, settling times for the cleaning agent, flushing/rinsing, etc.) would also occur in parallel, thus obviating the necessity to constantly walk back and forth between cock and beverage container for one line at a time. This results in significant time savings and even more operating convenience. Also, there is an increased efficiency of equipment utilization and a corresponding material savings since a multiline configuration only requires the change valve for each beverage line and the necessary connecting lines.
There is also an enhanced flexibility to the system according to the present invention. A multiline configuration does not necessarily require the cleaning of each beverage line connected. Any line within the system may remain uncleaned if desired. As long as the drafting cock for the line in question is not opened during the cleaning operation for the other lines, the original beverage "standing on the line" under CO.sub.2 pressure will remain in the line undisturbed. In this manner, a line with rarely dispensed beverage may be cleaned at less frequent intervals, reducing the amount of chemical cleaning agent used.
If the previously described restriction of not dispensing beverage but initiating the cleaning process by opening the drafting cock when the system is switched to the "cleaning" position is undesirable, a further aspect of the system of the present invention resides in the fact that, in the case of multiline dispensing systems, each line, starting with the second line, is equipped with a change valve and an expansion block. Each expansion block, in turn, incorporates a normal position solenoid valve as well as connections for the hydraulic set-water line and the cleaning agent line leading to the appropriate change valve. The expansion block further incorporates fittings to connect to the common water line, drain and cleaning agent line of the base block and/or the adjacent expansion block for the next beverage line. Thus, a direct in-line connection from the base block with the three solenoid valves to an infinite number of expansion blocks exists.
The additional benefit of this system expansion capability is the fact that each expansion block only requires one solenoid valve, the normal position valve. Assuming further that each line now has a separate switch on the central control console to move its piston into the normal or drafting position, it becomes easy to select the lines to be cleaned and the ones not to be cleaned during a particular cleaning process. The construction of this aspect allows for an easy and cost efficient way of expanding the base system by simply interconnecting the appropriate number of expansion blocks.
The present invention also provides for the integration of a separate switch next to each tapping cock of a drafting system. This is entirely optional since the appropriate switches for each line may also be incorporated in the central control console.